70 - Effect of Antenatal Corticosteroids on Newborn Screening for Congenital Adrenal Hyperplasia in Preterm Infants <34 Weeks in an Urban Multiethnic Hospital

Publication Number: 2067.70

Shyamkumar Panchani, Flushing Hospital Medical Center, Parsippany, NJ, United States; Bilal Manzoor, Flushing Hospital Medical Center, Flushing, NY, United States; Simin Kunwar, Flushing Hospital Medical Center, Flushing, NY, United States; Lily Q.. Lew, Flushing Hospital Medical Center, Flushing, NY, United States; Ignacio J. Contreras, Flushing Hospital Medical Center, Flushing, NY, United States

Background: Maternal antenatal steroids (ACS) are used to accelerate fetal lung maturation in pregnancies at risk for preterm delivery. Elevated 17-hydroxyprogesterone (17OHP) on newborn screening (NBS) suggests congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency. False positives and false negatives have been reported in preterm infants.

Objective: To explore the effect of ACS on NBS for CAH in preterm newborns < 34 weeks.

Design/Methods: A retrospective chart review of preterm neonates < 34 weeks gestational age (GA) born between October 1, 2020 and February 28, 2025 was performed. Data extracted from EHR included demographics (age, ethnicity), maternal ACS, GA, mode of delivery, gender, birth weight (BW), NBS, 17OHP levels, number of NBS, days of life needed to exclude CAH. Neonates were grouped according to GA ( < 28 weeks, 28- < 32 weeks, 32- < 34 weeks) and compared. Data were analyzed using R software, using linear mixed-effects model, a p value < 0.05 was considered significant.

Results: Of 231 neonates, most were in GA 32- < 34 weeks (n=113, 49%), fewer in GA 28- < 32 weeks (n=84, 36%) and the least in GA < 28 weeks (n=34, 15%). Overall, there was equal number of females (n=117, 51%) as males; half were Asian (n=116, 50%) followed by Hispanic (n=89, 39%) in ethnicity; almost a quarter (n=50, 22%) was twin gestation and three quarters (n=174, 75%) delivered by cesarean section. About a quarter (n=9, 27%) NBS performed at 24 hours of life screened positive for CAH in GA < 28 weeks, in a fifth (n=16, 19%) in GA 28- < 32 weeks and the least (n=12, 11%) in GA 32- < 34 weeks, p=0.274. There was no significant difference in the mean total ACS dose (2.00, SD=1.16 vs 2.10, SD=1.02; p=0.572), dexamethasone dose (p=0.766), or betamethasone dose (p=0.397) between the positive and negative groups. Mean (SD) GA was lower (29.3[2.8]) in those with elevated 17OHP compared to those with normal 17OHP (31.0[2.3]), p< 0.001. Mean (SD) GA was lower at first ACS dose (28.1[3.2] vs 29.6[3.2], p=0.01], and at last ACS dose (28.9[3.0] vs 30.4[2.6], p=0.002) in those with elevated 17OHP. The mixed-effects model showed that 17OHP levels decline with increasing age (p=0.001) and across subsequent draws (p=0.02). The total ACS dose, ethnicity, BW, and GA at birth were not significantly associated with the rate of 17OHP change.

Conclusion(s): Elevated 17OHP as screen positive on NBS was associated with lower GA and not associated with total dose of ACS received or time of last dose of ACS. Level of 17OHP declined with increasing age in those without CAH.